Metformin has long been the first-line drug of choice for treating type 2 diabetes. While insulin may be better known (it’s been available since the 1920s), metformin was introduced in the UK in 1958 (FDA approval in the U.S. occurred in 1995), and metformin is now believed to be the most widely prescribed anti-diabetic drug in the world.
More recently, a tantalizing new use for metformin has begun to emerge.
Over the past decade or so, scientists at the University of Texas MD Anderson Cancer Center, UCLA, UC San San Diego, and elsewhere have demonstrated that metformin also has interesting anti-cancer effects under certain circumstances. As MD Anderson researcher Aung Naing put it, “This oldie for endocrinologists is the new kid on the block for oncologists.”
About a year ago, UCLA researchers Richard Pietras and Michael Jung produced some “compelling data” on the use of metformin in mouse models of triple-negative breast cancer and pancreatic cancer, according to David Campbell, a longtime San Diego biotech executive.
“The data have not been published yet,” said Campbell, who has been an entrepreneur-in-residence at San Diego’s Avalon Ventures for the past two years. “The only way one can see the data is to sign a confidentiality agreement with UCLA.”
Nevertheless, the data were promising enough for Avalon and TPG Biotech to co-lead a $15 million Series A investment in Enlibrium, a San Diego biotech founded only about four weeks ago to advance new compounds based on the anti-cancer activity of metformin. San Diego’s Correlation Ventures and Osage University Partners also participated in the deal.
The financing is expected to provide enough capital to advance Enlibrium’s lead compounds through Phase 1 clinical trials. The company also intends to identify biomarkers that could be used to optimize the use of its compounds on various cancers.
Campbell, whose resume includes stints at Phenomix, RQx Pharmaceuticals, Afraxis, Sitari, and others, has taken the helm as Enlibrium’s CEO.
The underlying idea is that cancer cells typically shift into a kind of metabolic overdrive—using inordinate energy to drive the out-of-control proliferation of cancer cells. Campbell explained that with certain cancers, metformin appears to act like a kind of carburetor choke valve that strangles this process.
“Cancer cells are high-performance engines that have a hard time adjusting to a change in the ATP cycle, for example,” Campbell said, referring to the role adenosine triphosphate plays in transporting chemical energy within cells. In the presence of metformin, Campbell said some cancer cells “end up in a state of energetic crisis, and they go into apoptosis,” or programmed cell death.
Scientists have shown that metformin can
